Field of the Invention
The present invention relates to an evaluation method and evaluation apparatus of an epitaxial wafer, and, in an aspect, relates to an evaluation method and evaluation apparatus of an epitaxial wafer that are capable of detecting, with a high sensitivity, defects and/or foreign substances of various shapes and sizes.
Furthermore, the present invention relates to epitaxial wafer which the evaluation according to the evaluation method has been performed.
Discussion of the Background
Methods based on a light point defect (LPD) that is detected with a laser surface inspection apparatus are widely used as an evaluation method of defects and/or foreign substances of a semiconductor wafer (for example, see Japanese Patent No. 3664134 or English language family member U.S. Pat. No. 6,726,319, Published Japanese translation of PCT patent application No. 2004-531735 or English language family member WO2003/001.186, Japanese Unexamined Patent Publication (KOKAI) No. 2010-129748, and Japanese Unexamined Patent Publication (KOKAI) No. 2001-153635, which are expressly incorporated herein by reference in their entirety). In the above methods, by causing light to enter a surface of a wafer to be evaluated and by detecting radiation light (scattered light and reflected light) from the surface, the presence or absence of defects of the wafer and/or foreign substances adhering to the surface, that is, surface deposits, of the wafer as well as the size thereof can be evaluated.